Mechanism for step-by-step feeding of band-like members



July 17, 1962 N, G. E. STEMME 3,044,678

MECHANISM FOR STEP-BY-STEP FEEDING OF BAND-LIKE MEMBERS Filed May 18. 1959 x FIG.1

FIG.3

1 I 3L 6 A N l/[ N 7 /V/'/5 6 LC. STW/Wa A TTOQA/EKS p 3,044,678 Patented July 1 7, 1952 This invention relates in general to a mechanism for step-by-step feeding of band-like members and refers particularly to feeding mechanisms of a type operating at a very high speed and in which each feeding step is very accurate in respect of its length.

The invention is'of special importance for data processing machines and the like of a type operating in dependence on magnetizable bands or tapes to be perforated which for being magnetized and perforated respectively must be fed stepwise or intermittently at a very high speed and an extent per step which is accurately determined and must not deviate from a given value.

The mechanism according to the invention is substantially characterized in that it comprises control means for alternatively retaining the tape and forcing a clamping and feeding member into engagement with the tape re spectively so that the tape is caused to participate intermittently in the motion of the clamping and feeding member.

One embodiment of the invention is diagrammatically illustrated in the accompanying drawing by way of an example in which the invention is applied to a mechanism for step-by-step feeding of a tape intended to be used in data processing machines or the like and to be punched with coded information.

FIG. 1 is a partial cross-sectional view of a mechanism according to the invention. I

FIGS. 2 and 3 show a detail on an enlarged scale. 7

Referring to FIG. 1 of the drawing, 1 designates a lower base plate provided withbrackets 2 and bars 3; and 4 designates an upper base plate to which guides 5 for the tape 6 to be fed and perforated are attached. Pivotally mounted on rod ll) in brackets 2- on the lower base plate 1 is a lever 9. A link 11 is eccentricallyjournalled on themain shaft 12 of the mechanism this link being, by means of a pin 13, also rockably connected to the lever 9 in such a way that during the rotation of the main shaft 12 said lever 9 is oscillated about the pivot 10. As appears most clearly from FIG. 2 (which shows the upper portion of the lever 9 and adjacent details on an enlarged scale and in which the vertical dimensions for the sake of clearness have been considerably magnified), the upper end 14 of the lever 9 is bent at a right angle and with a plate 15 secured to the lever, forms a passage 16 for the tape 6. It maybe seen that the passage 16 is constructed of members unitarily formed on oscillating lever 9. By unitarily formed on is means that such members are formed on the end of and as a part of oscillating member 9 and arcuately oscillate therewith as distinguished from elements which may be actuated by the end of oscillating arm 9. The upper end id of member 9 is formed with an upper surface li7 which is arcuate and forms a portion of a cylinder, the radius of curvature of which is the distance between the upper surface and the rod or pivot ill. As will appear later, the upper surface 17 is designed to mate with a similar curved surface formed on a member 34 so that the tape 6 may be clamped between a plate 15 fixed to lever 9 and the member 14, which members 14 and15 comprise a feeding clamping means for causing the tape to participate in the feeding action of the lever 9. Since,

as will later appear, the surface 36 of member 34 bears against the surface 17 of member 14 only during the feeding movement and not during the return movement, the

feeding of the tape heretofore mentioned occurs and the tape 6 is fed over a punch die 19 on which the tape is perforated by means of punches (not shown) actuated selectively and arranged to move upwards and downwards in a guide 20.

The mechanism comprises further a retaining member consisting of a clip or stripZl (see also FIG. 3) attached immediately above the tape and fastened tothe upper base plate 4 by means of leaf springs 22 secured by screws 23 There are further provided a pair of electromagnets 25, 26 to which impulses from an impulse source (not shown) are applied, said electromagnets 25, 26 being spaced apart forming a gap in which an armature 27 common to both electromagnets is movably disposed. The said armature forms a portion of a control means 28 which may be seen to be a unitary lever having three arms, one of said arms forming armature 27 which together with the remaining two of said arms are arranged to be pivoted one pivot axis 29 into two fixed end positions in dependence of the magnetization of the magnets 25, 25. The saidpivot axis 29 extends substantially perpendicularly to the feeding direction of the tape 6 and is located in a plane perpendicular to said direction and passing through the center of the space between magnet-s 25, 26. A pressure device is attached to the end of each arm of said lever and cooperate with the retaining member 21 and the clamping and feed ing member 9-17 respectively.

The pressure device cooperating with the retaining member 21 comprises a screw 31 having a rounded end adapted to abut against the retaining clip 21 in the one end position of the control means, together with alock nut 32 for retaining screw 31 in an adjusted position. The pressure device cooperating with the clamping and feeding members 9 to 17 comprises a screw 33 having a pressure plate 34 attached to its lower end, together with lock nut 35. Owing to this construction, the pressure devices 231, 32and 33-36 respectively can be set individually. The lower surface 36 (FIG. 2) of the pressure plate 34 which is intended to abut against the upper surface of the upper end 14 of lever 9 when the control means reaches its other end position, forms a portion of a cylinder the axis of which is pivot axis ltlof the lever 9. In this position the surfaces 17 and 36 are thus concentric and immediately adjacent one another.

Whenever the lever '9 pivots in counter clock-wise direction and, consequently, the plate 15 is displaced from the right to the left, the coil of magnet 25 receives an impulse. Correspondingly, an impulse is applied to the coil of magnet 26 each time the lever 9 pivots clockwise direction and plate 15 is displaced from the left to the right. or transferred from its first fixed end position in which the pressure device 31, 32 cooperates with the retaining clip 21, to its second fixed end position in which the pressure device 33- 36 cooperates with the clamping and feeding members 9 to 17 at the same time as the lever 9, its upper, bent end portion 14 and plate 15 are in the left end position.

In a similar manner, the control means 28 is shifted from its second fixed end position in which the pressure device 33-35 cooperates with the clamping and feeding members 9 to 17 to its first fixed end position in which the pressure device 31, 32 cooperates with the retaining clip 21 at the same time when the lever 9, its upper, bent end portion 14 and plate 15 are in the right end position. In order to guarantee the synchronous oscillation of the lever 9 and the control means 28, a synchronizing device is preferably provided. This device may have the form of a pointer consisting at least partially of magnetic material, which is fastened on the shaft 12 and in two di- The control means 28, accordingly, is shifted ametrically opposite positions passes with its magnetic portion through air gaps each comprised in its magnetic circuit. Each one of the two last mentioned magnets is linked to a coil in which voltage pulses are induced owing to the flux variations caused by the passage of the pointer through the respective air gap. The said voltage pulses may then be utilized as a timing means for the impulses applied to the coils of the electromagnets 25, 26.

The described mechanism operates in the following manner:

When magnet 25 is energized the pressure device 31, 32 holds the tape 6 clamped between the retaining clip 21 and the upper base plate 4, and the members 9, 14 and 15 move freely to the left in relation to tape 6 into the left end position. When magnet 26 is energized, the control means 28 is shifted to its other (right) fixed position in which the pressure device 31, 32 is inactive and the pressure device 33-36 clamps the tape 6 between the members 14 and 15 of the clamping member (see FIG. 2). Upon continued rotation of the main shaft 12, members 14 and 15 together with lever 9 move to the right, and tape 6. participates in this motion owing to the fact that the cylindrical surface of the bent end portion 14 slides against the cylindrical surface of the pressure plate 34 so that the compressive force between said surfaces remains constant. When lever 9 has reached its end position on the right, the control means 28 is transferred whereafter the cycle described is repeated.

The described embodiment of the mechanism provides among others the advantage that the acceleration and retardation of tape 6 occurs about sinusoidally so that the tape is not subjected to tensions which may be too high owing to the accelerating and retarding motions of the feeding member.

The embodiment described and shown must of course be considered to be only as an example the details of which may be modified in various ways within the scope of the following claims. The motion of the clamping and feeding member, for example, can be attained in a different way, for instance by means of a pin engaging in a inclined groove on a rotating ratchet Wheel having an axis running parallel to the feeding direction of the tape. The mechanism according to the invention may of course also be used for step-by-step feeding of oblong articles other than bands to be magnetized and tapes to be perforated or the like for data processing machines. As further examples of such oblong articles can be mentioned ribbons, rods and tubes of any optional material.

What I claim is:

A step-by-step feeding mechanism for tapes and the like comprising, in combination, a reciprocating feeding member, feeding clamping means comprising normally released friction means on said feeding member for clamping the tape for drive by said member, retaining means for frictionally clamping the tape between strokes of the feeding member, a unitary lever having at least three arms and two positions, said lever being mounted on an axis substantially perpendicular to the feeding direction of the tape, means on a first arm of said lever for rendering said retaining means operative in one position of the lever, means on a second arm of said lever for rendering said feeding clamping means operative in the second position of said lever, and electromagnetic means acting on the third arm of said lever for alternately placing said lever in said positions to thereby alternately retain and feed the tape, said reciprocating feeding member being continuously operable independently of the position of said lever.

2. A step-by-step feeding mechanism for tapes and the like comprising, in combination, a reciprocating feeding member, feeding clamping means comprising normally released friction means on said feeding member for clamping the tape for drive by said member, retaining means for frictionally clamping the tape between strokes of the feeding member, a lever having at least two arms and two positions, said lever being mounted on an axis substantially perpendicular to the feeding direction of the tape, means on a first arm of said lever for rendering said retaining means operative in one position of the lever, means on a second arm of said lever for rendering said feeding clamping means operative in the second position of said lever, and electromagnetic means for alternately placing said lever in said positions to thereby alternately retain and feed the tape, said reciprocating feeding member being continuously operable independently of the position of said lever, and said feeding member compris ing a pivoted arm and said feeding clamp means comprising a fixed and a resilient member unitarily formed on one end of said pivoted arm, the tape passing between said fixed and resilient members, said resilient member being actuated by said lever in the second position thereof to press the tape against the fixed member to thereby clamp the tape for movement with said feeding member.

References Cited in the file of this patent UNITED STATES PATENTS 315,882 Arnold Apr. 14,1885

421,195 Ross et al. Feb. 11, 1890 1,733,834 Steele Oct. 29, 1929 2,263,721 De Lorme Nov. 25, 1941 2,772,325 Gaite Nov. 27, 1956 2,803,455 Powers Aug. 20, 1957 2,848,223 Birchler Aug. 19, 1958 2,946,588 Pityo July 26, 1960 

